Garbage Disposal Not Working: Troubleshooting Guide

Garbage Disposal Not Working: Troubleshooting Guide
Quick Answer

Most garbage disposal problems can be fixed in minutes without a plumber. Press the red reset button on the bottom of the unit, then use a 1/4-inch Allen wrench in the bottom port to manually rotate a jammed flywheel. If the unit is completely dead, check that it’s plugged in and the circuit breaker hasn’t tripped.

Before calling a plumber or buying a new disposal, try these simple fixes. Most issues are caused by overloading, foreign objects, or a tripped thermal overload—all easily resolved.

What You’ll Need

Tools:

  • 1/4-inch Allen wrench (or InSinkErator wrenchette)
  • Flashlight
  • Tongs or needle-nose pliers
  • Wooden broom handle (backup method)

Quick Diagnosis

SymptomLikely CauseSolution
Completely dead (no sound)No power or tripped resetCheck outlet, breaker, press reset
Humming but not spinningJammed flywheelUse Allen wrench to free
Leaking from bottomCracked internal sealsReplace unit
Grinding slower than usualDull blades or buildupClean or replace

Scenario A: Disposal Completely Dead

FIRST: Safety Check

  1. Turn OFF wall switch
  2. Unplug unit from outlet (or flip circuit breaker if hardwired)
  3. NEVER put your hands inside the disposal

Troubleshooting Steps:

  1. Check power connection — Ensure plug is secure in outlet (easily bumped loose under sink)
  2. Test outlet — Plug in a lamp to confirm the outlet has power
  3. Check circuit breaker — Look for tripped breaker in main panel; flip back to ON
  4. Press reset button — Locate on bottom of unit; press firmly once
  5. If button won’t stay in, wait 10-20 minutes for unit to cool, then try again
  6. Test: Run cold water, turn on disposal

Scenario B: Humming But Not Spinning

A humming disposal means the motor is getting power but the flywheel is jammed. Turn it off immediately—prolonged running burns out the motor.

  1. Cut all power (unplug or flip breaker)
  2. Allow unit to cool 5-10 minutes
  3. Insert 1/4-inch Allen wrench into center hole on bottom of unit
  4. Turn wrench back and forth firmly until flywheel rotates freely in complete circles both directions
  5. Alternative method: Insert wooden broom handle through drain opening, press against impeller blade, work back and forth
  6. Use flashlight to check for foreign objects
  7. Remove debris with tongs or pliers (NEVER hands)
  8. Restore power, press reset button
  9. Run cold water, quickly flip switch on/off to clear debris
Pro Tip

Always run cold water when operating your disposal—hot water liquefies grease, which then solidifies further down the drain and causes clogs.

What NOT to Put in Your Garbage Disposal

Avoid these items to prevent jams and damage:

ItemWhy It’s a Problem
Fibrous vegetables (celery, asparagus, corn husks)Long fibers wrap around impellers
Starchy foods (pasta, rice, potato peels)Expand when soaked; create sticky clogs
Grease and oilSolidifies in pipes; causes 65% of sewer overflows
Bones (except small chicken bones)Too hard; can bend or break blades
Coffee groundsForm dense, packed paste in drain lines
Egg shellsMembrane wraps around impellers
Fruit pits (peach, avocado, cherry)Too hard to grind
Non-food itemsTwist ties, rubber bands, glass, plastic

Rule of thumb: If you can’t cut it with a knife, the disposal can’t process it.

Signs It’s Time to Replace

SignWhat It Means
Frequent resets (multiple times/week)Motor struggling
Persistent foul odorsBuildup in housing
Water leaking from bottomCracked internal seals
Grinding takes longerDull blades
Humming after clearing jamsDead motor
Unit is 10+ years oldEnd of service life

When to Call a Pro

Call a plumber or electrician if:

  • Reset button won’t stay pressed after multiple attempts
  • Disposal smokes when turned on (motor is fried)
  • Motor hums even after clearing all visible jams
  • Persistent leaking from bottom of unit
  • Circuit breaker continues tripping
  • Unit is over 10 years old with recurring issues

Common Mistakes to Avoid

  • Putting hands inside — Even unplugged, impellers can cut; short circuits can occur
  • Running without water — Always run cold water during and 15-30 seconds after
  • Overloading — Feed small amounts at a time
  • Using hot water — Melts grease which re-solidifies in pipes
  • Not running regularly — Causes rust and corrosion
  • Using harsh chemicals — Bleach and drain cleaners damage seals

Frequently Asked Questions

Where is the reset button on a garbage disposal?

The reset button is on the bottom or side of the disposal unit—a small red button about the size of a pencil eraser. When tripped, it protrudes about 1/4 inch from the housing. Press it firmly once to reset.

What size Allen wrench do I need for a garbage disposal?

Most garbage disposals use a 1/4-inch (6mm) hex Allen wrench inserted into the center hole on the bottom of the unit. InSinkErator disposals include a silver “wrenchette” tool. Turn back and forth to free a jammed flywheel.

How long do garbage disposals last?

Garbage disposals typically last 8-15 years, with 12 years being average. Higher-horsepower stainless steel units last 10-15 years. Signs it’s time to replace: frequent resets, persistent odors, water leaking from the bottom, or grinding takes increasingly longer.

HT

Written by HomeFixBasics Team

Our team of home maintenance experts provides practical, actionable advice to help homeowners tackle common repairs and maintenance tasks.